Ultrasonic imaging is known in the art and systems typically involve the use of a hand-held or temporarily affixed ultrasonic transducer element or transducer array that may be controlled, for example, as to on/off, mode, focus control, depth control and the like. A qualified user applies a small amount of ultrasound gel to a region of interest, holds and moves the ultrasound transducer from one location of the patient to another within the region, the unit being wired to a console, typically including a display. The ultrasound transducer is housed in a wand that may be moved about the patient's body surface to obtain two dimensional, three dimensional or so-called four dimensional (including movement over time of the subject of the imaging) views provided on a display of the console of the region of interest. It is generally known that one may improve the image by moving the wand slightly, for example, to avoid reflections from internal body parts that are not of interest and thus obtain an improved image of a body part, such as the heart, that is of greater interest and to obtain a stronger reflected signal from the heart. Ultrasound is a biologically safe and non-radiating form of energy that can provide detailed anatomic and, in some cases, functional images. It is known in the art of transesophageal echocardiography (imagery of the heart) to provide a multi-plane transducer that can image in planes in a 180 degree range.
The advent of piezocomposite material comprising a piezoelectric ceramic and a polymer has improved performance of commonly used ultrasonic arrays. Ultrasonic arrays may be annular, rectangular (linear) and two, three or four dimensional where the fourth dimension represents movement over time in a three dimensional space. While originally analog, ultrasound imaging is now digital in order from transducer to beam former, signal processor, scan converter and a monitor or display. Imaging is similar to television reception as scan lines of an image are produced at a depth of field given by the equation 6×λ×(FN)2 where FN is the ratio of focal depth and aperture and λ is the wavelength. A plurality of lines of ultrasound picture elements (pixels) comprise a frame and a typical frame rate is 30 frames per second. For example, a transducer operating at 10 MHz operating at an f-number of 15 yields a depth of focus of about 2 cm. In a phased-array system, elements of an array are used for each interrogation pulse and various time delays are introduced between the elements. Beam steering is accomplished by varying the time delays of the individual elements. A linear array is a stacking of adjacent elements linearly, for example, 512 elements over a 75 to 120 mm length. Subgroups of elements are pulsed in delay relation to other subgroups. Distinguished from linear arrays, annular (circular) arrays vary in construction. An electronically steered-beam, phased-array has proven useful in cardiac imaging. On the other hand, phased-array transducers have not seen as extensive use as linear sequenced arrays in general ultrasound medical imaging. Real-time four dimensional imaging is known for providing motion imaging of a three dimensional space such as a pericardial cavity. Specialty arrays are known, for example, a curvilinear or convex abdominal transducer is known for providing an improved fit to an obstetric abdomen. The term “array” as used herein may be defined as a plurality of transducer elements in any one of a plurality of forms suitable to a particular purpose. Harmonic imaging is known for the transmission of a first frequency and the reception of reflections at a harmonic of the transmitted first frequency. The lower frequency transmission improves depth of penetration and the higher harmonic reception improves imaging particularly in imaging more obese patients.
Ultrasound operates on a principle of transmitting a sound wave of a given frequency range and recording the time and value of reflected wave data of a principal frequency and its harmonics from body parts of interest to the qualified user. Similarly, optical coherence tomography (OCT) utilizes a similar transmission/reflection process by transmitting light waves and recording the reflected light amplitude and delay. Light, however, may only penetrate a body to a depth of a few millimeters. Consequently, OCT has proven useful, for example, for quantifying the depth and healing over time of a third degree skin burn and underlying regions. Another field of medical imaging is infrared medical imaging where infrared energy is passively emitted by a body and provides an indication of temperature of the region imaged. An infrared camera captures the images of the infrared emission gradients which can be calibrated to show differences in temperature of adjacent regions, for example, as a yellow, orange, red scale. Infrared imaging has been found useful for imaging breast tumors and other close to the skin surface abnormalities indicated by temperature gradient.
U.S. Pat. No. 4,554,927, issued Nov. 26, 1985 to Fussell describes pressure and temperature sensors for biomedical applications wherein the sensor can be inserted into a body transcutaneously by a catheter.
It is also known, for example, in the telecommunications arts to remotely transmit images such as photographic images from a source such as a cellular telephone device equipped with a camera to a receiving cellular telephone or other telecommunications device. For example, a doctor may transmit a digital image to another doctor by attaching the image to an email. An x-ray machine located in a remote laboratory may capture an image of a broken bone, and the technician may immediately transmit the image to an orthopedic unit of a hospital for analysis. Cellular telephone devices are now capable of capturing and transmitting moving images, including movies with associated sound, for personal enjoyment.
PCT/US08/71943, filed Aug. 1, 2008, by the same inventor provides considerable detail of wired and wireless remotely controlled ultrasound imaging devices that may be surface-mounted to an animal body and used in combination with an image-guided catheter for minimally invasive medical procedures. FIG. 1 provide exemplary embodiments of a wired or wireless remotely controlled transducer; FIGS. 2-3 provide an exemplary electronic circuit and mechanical diagram, respectively, for a wireless transducer incorporating rotation, linear movement in two directions and twist; and FIG. 7 provides an embodiment combining an image guided transducer for minimally invasive medical procedures with a wireless transducer. U.S. patent application Ser. No. 12/182,247, filed Jul. 30, 2008, of the same inventor provides similar details.
U.S. patent application Ser. No. 11/871,282, filed Oct. 12, 2007, of the same inventor provides details of an image guided ultrasonic catheter and methods of use. FIG. 1 show an image-guided catheter having an anchoring portion 218 slidably mounted to the catheter for fixing the catheter to skin surface of a body. PCT/US07/81185 filed Oct. 12, 2007, of the same inventor provides similar details.
U.S. patent application Ser. No. 11/871,219 filed Oct. 12, 2007, of the same inventor provides details of an anchoring portion of an ultrasound image guided catheter having first and second deployable balloons for positioning the image guided catheter so as to be fixed to an internal body wall such as a pericardial wall for minimally invasive medical procedures.
U.S. patent application Ser. No. 11/782,991, filed Jul. 25, 2007, entitled “Image Guided Catheters and Methods of Use,” of the same inventor describes a plurality of embodiments of an image guided catheter that may be used, for example, to image an area of the thoracic cavity such as the heart or other region of interest and deliver medication, treatment and the like accompanied by ultrasonic and other imaging with an ultrasonic array mounted towards a distal end of a catheter. The catheter is provided with a plurality of lumen running from a proximal to the distal end. Interventional, diagnostic or therapeutic devices may be inserted via a sheath to the region of interest.
U.S. Pat. No. 5,465,724, issued Nov. 14, 1995 to Sliwa, Jr. et al. discloses a compact rotationally steerable ultrasound transducer having a circular track or a carrier band operable to rotate a multi-element transducer, for example, for transesophageal echocardiography. U.S. Pat. No. 5,454,373 issued Oct. 3, 1995 to Koger et al. describes a rotatable drive shaft of an ultrasound imaging device having a tubular body and a nose member which includes the ultrasound imaging device and connected to the rotatable drive shaft for rotation to obtain different internal views, for example, of a blood vessel. Alternatively, U.S. Pat. No. 5,701,901 issued Dec. 30, 1997 to Lum et al. discusses a pivotable reflector for reflecting an axially-directed ultrasonic beam in a radial direction per FIG. 5.
U.S. Pat. No. 5,997,497 issued Dec. 7, 1999, to Nita et al. discusses use of a foot petal on/off switch for hands-free actuation of a signal generator connected to an ultrasound transducer. U.S. Pat. No. 7,127,401 issued Oct. 24, 2006 to Miller describes remote control of a medical imaging device using speech recognition as well as foot controls. In particular, a surgeon using an ultrasound imaging console may speak a command, for example, “zoom,” and a speech recognition processor receives the voiced command for comparison with a look-up table, and, the functionality being available at an associated control console, magnification of a displayed image may be provided to the surgeon. United States Patent Application, US 2002/0065464, published May 30, 2002, describes an imaging device including a wireless mobile unit. Ultrasonic imaging devices and viewing apparatus are large and bulky apparatus. The described imaging device allows an operator to move freely throughout the operating arena, without being tangled within cords and allowing the patient to remain relatively undisturbed while simultaneously allowing the operator full access to the entire patient's body. United States Patent Application, US 2007/0066894, published Mar. 22, 2007, describes a remote wireless control device for an ultrasound machine and method. The remote wireless control device includes a subset of controls present on larger apparatus including a sonogram display. A smaller mobile unit communicates with the larger unit and may be more easily used bed-side than the larger apparatus.
U.S. Pat. No. 6,558,326 issued May 6, 2003 to Pelissier describes a plurality of ultrasound imaging systems connected to a network according to FIG. 7 which may be a local area network or a wide area network or combination for communicating with a server and a plurality of clients to provide various services such as report generation, tele-exam, remote control, and patient database administration.
Methods and apparatuses for providing three dimensional ultrasonic imaging are known. U.S. Pat. No. 6,572,551 issued Jun. 3, 2003 to Smith et al. describes a three dimensional ultrasound imaging probe configured to be placed inside a body. Published Canadian Patent Application 2 376 103 of Glaser et al. dated Jan. 4, 2002, discusses obtaining three dimensional images by ultrasonic scanning from a minimum of two different positions based on three different send-receive cycles or an arrangement of three acoustic modules and two send-receive cycles, not arranged collinear to each other.
U.S. Pat. No. 7,118,531, issued Oct. 10, 2006, to Krill describes an ingestible medical payload carrying capsule with wireless, e.g. ultrasonic, communication to transducers placed on a patient. The capsule may deliver medication or contain imaging apparatus such as an optical camera and/or a transducer with a pulse driver for internal acoustic pulse illumination and external high resolution sonogram imaging and detection.
U.S. Pat. No. 7,115,092, issued Oct. 3, 2006, to Park et al. describes a micromanipulator useful for ultrasonic imaging systems capable of generating a scanning motion so that front images in various angles can be captured. The micromanipulator can provide up to ±40° of angular deflection, with two degrees-of-freedom, which would provide full 3-D scanning motions. Preferably, the micromanipulator has a tubular structure with at least one compliant mechanism formed from an elastic or superelastic material. These tubular structure can preferably be substituted with pliable needle channel portions or a pre-stressed guide wire introduced through a separate lumen to cause the distal tip to point in a different direction. Such structures are known to be useful in intravascular ultrasound imaging and intervention.
Each of the above-identified patents and patent applications should be deemed to be incorporated by reference herein as to their entire contents.